1) request
the package;
2) unpack
it in your working directory;
3) create
a file "mos.dat"
appropriate for your version of IDL.
Under Unix, create a link
ln -s mos_54.dat mos.dat
if you run IMDI under IDL version 5.4.
Under Windows, just copy (for instance) mos_54.dat to "mos.dat".
4) Type
"idl mos" to start IMDI.
Please request the most recent version of the IMDI executable code for IDL 5.2, IDL 5.3, IDL 5.4 to the DOLoRes Staff Astronomer.